Is Cortisol A Progesterone Antagonist?

[success23]

Is it?

 

[matisvijs]

Well, progesterone is a cortisol antagonist, so any time your progesterone is low, your cortisol will be high (and vice versa). I don't know, however, if cortisol directly antagonizes progesterone (the cortisol could go up because progesterone was lowered by other factors vs cortisol going up lowering progesterone by itself). So cortisol and progesterone levels definitely have an inverse relationship, it's just not clear to me whether it's direct (in the case of cortisol lowering progesterone).

 

[haidut]

Is it?

Mostly yes, both at the receptor level and functionally. The PR and GR have about 80% overlap in structure/composition so it is not surprising that this is happening. The second stud below is really interesting because it shows that cortisol has pro-inflammatory effects as well, which explains why it accelerated so much the decline of patients with autoimmune conditions and cancer. If you ask a doctor if cortisol causes inflammation he/she will probably kick you out of the office
Cortisol blockade of progesterone: a possible molecular mechanism involved in the initiation of human labor. - PubMed - NCBI
A quantitative comparison of dual control of a hormone response element by progestins and glucocorticoids in the same cell line. - PubMed - NCBI
Mechanism of Cortisol/Progesterone Antagonism in the Regulation of 15-Hydroxyprostaglandin Dehydrogenase Activity and Messenger Ribonucleic Acid Levels in Human Chorion and Placental Trophoblast Cells at Term